GeSb$_{2}$Te$_{4}$ Structure: AB2C4_hR7_166_a_c_2c-002

Picture of Structure; Click for Big Picture
Prototype GeSb$_{2}$Te$_{4}$
AFLOW prototype label AB2C4_hR7_166_a_c_2c-002
ICSD 30393
CCDC 1604732
Pearson symbol hR7
Space group number 166
Space group symbol $R\overline{3}m$
AFLOW prototype command aflow --proto=AB2C4_hR7_166_a_c_2c-002
--params=$a, \allowbreak c/a, \allowbreak x_{2}, \allowbreak x_{3}, \allowbreak x_{4}$

Other compounds with this structure

GeAs$_{2}$Te$_{4}$,  GeBi$_{2}$Te$_{4}$,  PbBi$_{2}$Te$_{4}$,  PbSb$_{2}$Te$_{4}$,  SnBi$_{2}$Te$_{4}$,  SnSb$_{2}$Te$_{4}$,  TeS$_{2}$Bi$_{4}$,  BiSbSnTe$_{4}$,  Bi$_{2}$Sb$_{2}$Te$_{3}$


  • This structure is nearly identical to MnBi$_{2}$Te$_{4}$, but the assumed ordering of the tellurium atoms is different in the two cases.
  • We use the data from (Agaev, 1966) as reported by (Matsunaga, 2004), however the ICSD entry states that all of the (2c) sites have occupancy Te$_{0.66}$Sb$_{33}$. We follow (Matsunaga, 2004) and label the first (2c) site as Sb with the other two Te, preserving the stiochiometry.
  • The binary form of this structure is Sn$_{4}$P$_{3}$.
  • Hexagonal settings of this structure can be obtained with the option --hex.

\[ \begin{array}{ccc} \mathbf{a_{1}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{\sqrt{3}}{6}a \,\mathbf{\hat{y}}+\frac{1}{3}c \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{\sqrt{3}}a \,\mathbf{\hat{y}}+\frac{1}{3}c \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&- \frac{1}{2}a \,\mathbf{\hat{x}}- \frac{\sqrt{3}}{6}a \,\mathbf{\hat{y}}+\frac{1}{3}c \,\mathbf{\hat{z}} \end{array}\]

Basis vectors

Lattice coordinates Cartesian coordinates Wyckoff position Atom type
$\mathbf{B_{1}}$ = $0$ = $0$ (1a) Ge I
$\mathbf{B_{2}}$ = $x_{2} \, \mathbf{a}_{1}+x_{2} \, \mathbf{a}_{2}+x_{2} \, \mathbf{a}_{3}$ = $c x_{2} \,\mathbf{\hat{z}}$ (2c) Sb I
$\mathbf{B_{3}}$ = $- x_{2} \, \mathbf{a}_{1}- x_{2} \, \mathbf{a}_{2}- x_{2} \, \mathbf{a}_{3}$ = $- c x_{2} \,\mathbf{\hat{z}}$ (2c) Sb I
$\mathbf{B_{4}}$ = $x_{3} \, \mathbf{a}_{1}+x_{3} \, \mathbf{a}_{2}+x_{3} \, \mathbf{a}_{3}$ = $c x_{3} \,\mathbf{\hat{z}}$ (2c) Te I
$\mathbf{B_{5}}$ = $- x_{3} \, \mathbf{a}_{1}- x_{3} \, \mathbf{a}_{2}- x_{3} \, \mathbf{a}_{3}$ = $- c x_{3} \,\mathbf{\hat{z}}$ (2c) Te I
$\mathbf{B_{6}}$ = $x_{4} \, \mathbf{a}_{1}+x_{4} \, \mathbf{a}_{2}+x_{4} \, \mathbf{a}_{3}$ = $c x_{4} \,\mathbf{\hat{z}}$ (2c) Te II
$\mathbf{B_{7}}$ = $- x_{4} \, \mathbf{a}_{1}- x_{4} \, \mathbf{a}_{2}- x_{4} \, \mathbf{a}_{3}$ = $- c x_{4} \,\mathbf{\hat{z}}$ (2c) Te II

References

  • T. Matsunaga and N. Yamada, Structural investigation of GeSb$_{2}$Te$_{4}$: A high-speed phase-change material, Phys. Rev. B 69, 104111 (2004), doi:10.1103/PhysRevB.69.104111.
  • K. A. Agaev and A. G. Talybov, Electron-diffraction analysis of structure of GeSb$_{2}$Te$_{4}$, Sov. Phys. Crystallogr. 11, 400 (1966).

First cited in

  • H. Eckert, S. Divilov, M. J. Mehl, D. Hicks, A. C. Zettel, M. Esters, X. Campilongo, and S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 4, Comp. Mat. Sci. 240, 112988 (2024). (doi=10.1016/j.commatsci.2021.110450)

Geometry files


Prototype Generator

aflow --proto=AB2C4_hR7_166_a_c_2c --params=$a,c/a,x_{2},x_{3},x_{4}$

Species:

Running:

Output: